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-   -   well what do you know it was a 13B (https://www.rx7club.com/1st-generation-specific-1979-1985-18/well-what-do-you-know-13b-533135/)

shepski 04-24-06 01:35 AM

well what do you know it was a 13B
 
a while ago i bought a wrecked SA for 150 bucks still running with everything except the engine completely fucked.

i never really looked at the engine, just assumed its a 12A but when i went to put the headers off that engine on my other 12A they didnt fit. *gasp*

on closer inspection its actually a 13B with the rats nest gone. now from the rats nest removal i assume that it was probably an enthusiasts car plus it had headers and free flow exhaust. so what are the odds that its ported.

the clincher, how do i tell if its been ported, is there an easy way without starting it?

mr_ouija 04-24-06 01:37 AM

Tear it apart? Think that'd be the only way to know for sure.

rotary_sex 04-24-06 02:05 AM

the exhaust note will be obvious if its ported

Naegleria_Fowleri 04-24-06 02:06 AM

yeah, exactly. Tearing it apart. If you've gotten to drive a 13b non ported in an FB/SA before, you could drive the cars to figure out the power differences. Check the fuel pump, chances are if it was ported it would have an upgraded fuel pump (possibly). The only real way to tell is by tearing it apart though. Other things will just hint around to the possibility of whether it is ported or not.

Naegleria_Fowleri 04-24-06 02:07 AM


Originally Posted by rotary_sex
the exhaust note will be obvious if its ported

He can't/doesn't want to start it. Otherwise I would have mentioned that as well.

trochoid 04-24-06 02:08 AM

Pull off the intake and feel the runners. I can see and feel my bp with the intake off. If the runners are polished, good chance it has a port.

shepski 04-24-06 06:09 AM

yeah i cant start it at the moment, the carbs off coz im rebuilding it and i took the starter motor out to put in my other SA.

cheers for the advice, ill try trochoids suggestion when i see my car next.

vipernicus42 04-24-06 01:44 PM

show us pics!

13b's weren't carbed unless they came from earlier cars like the Rx3 or 4.

And I don't think those had "rats nests"

If it came from a GSL-SE, then I've gotta see how he mounted the carb.

Jon

shepski 04-24-06 09:10 PM

ok, i wasnt aware that 13Bs werent carbed, the carb wasnt actually mounted when i got it, it was sitting on the front seat, so maybe its just off another 12A?. ill get pics when i go to my old mans factory next (hours drive away and no license)

trochoid 04-24-06 09:20 PM

Take pics of the intake ports and the 13B logo on the housing. That will give an idea if it is a 74-78 or an SE with 12a end irons.

Edit*

Just realised you are down under, and you didn't get the SE motors there. Post pics anyway.

85rotarypower 04-24-06 11:20 PM


Originally Posted by vipernicus42
show us pics!

13b's weren't carbed unless they came from earlier cars like the Rx3 or 4.

And I don't think those had "rats nests"

If it came from a GSL-SE, then I've gotta see how he mounted the carb.

Jon

Just because it is carbed now doesn't mean it originally was a carbed engine. There are many different manifolds you can get to convert the 6 port engines from FC's and even FD's to carb. I've actually got a Jay-Tech manifold on my 88 6 port with a nice Edelbrock 600 cfm carb on top of it. Its very possible that this is the case with this engine.

As for checking for porting, just feel around in the intake ports of the engine. If its a 6 port engine, the lower secondary ports and the primary ports should feel like they drop down the further into the engine you go. They should also feel smooth. Feeling the intake ports is probably the best way to determine if an engine has been ported, but unless its a bridgeport of some sort, you won't be able to tell the extent of the porting.

vipernicus42 04-25-06 01:10 AM


Originally Posted by 85rotarypower
Just because it is carbed now doesn't mean it originally was a carbed engine. There are many different manifolds you can get to convert the 6 port engines from FC's and even FD's to carb. I've actually got a Jay-Tech manifold on my 88 6 port with a nice Edelbrock 600 cfm carb on top of it. Its very possible that this is the case with this engine.

As for checking for porting, just feel around in the intake ports of the engine. If its a 6 port engine, the lower secondary ports and the primary ports should feel like they drop down the further into the engine you go. They should also feel smooth. Feeling the intake ports is probably the best way to determine if an engine has been ported, but unless its a bridgeport of some sort, you won't be able to tell the extent of the porting.


That's why I want to see it.

Because I know there are no stock manifolds (among first gens anyway) to put a carb on a 13b.

And since he's from australia, his 13b isn't even from a first gen either!

So I definitely want to know which 13b he has, with which carb, on which manifold!

It could be as simple as a stock Rx4 13b swap including its carburetor. We won't know w/o pics.


Jon


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